Bottom hole inlet for plunger lift devices



Patented May 16, 1933 YUNITED STATES PATENT OFFICE NORMAN H. 310mm,orvenousron, 'rExAsassIeNoR mo HUGHES T001. COMPANY, or

noUs'roN, Times, A. CORPORATION or TEXAS BOTTOM, HOLE INLET FOR'PLUNGERLIFT DEVICES Application filed January 9, 1982. Serial No. 585,784.

My invention relates to plunger lift devices for use in raising liquidfrom deep wells and has reference particularly to devices in which theplunger is adapted to move from the lower end to the upper end of thewell,

carrying with'it aload of liquid which is discharged at the surface.

This device is an improvement upon the structure shown in my priorapplication 'Serial'No. 579,177, filed December 5, 1931.

It is an object of the invention to provide 1 a device whereby theliquid may be more.

effectively raised in the eduction tube through the gas coming'from theproducing formation. There are wells in which there is a fairly largehydrostatic drive which raises the liquid in the well so as to providesuflieient submergence, but due toithe'small quantity of gas produced bythe well the plunger cannot be operated withany speeddue to the slowproduction of gas. 7 H

I contemplate forming an extension at the lower end of the eduction tubethrough which the gas may rise and have a more effective lifting actionupon'theliquid in the well, due to decreased slippage in the smallerpipe.

I also desire to confine the gas inthe well to a space ofsmalldimensions? adjacent the lower end of the tube so tha-t it mayaccumulate more quickly and act more effectively without considerationfor the large chamber inthe casing above-the packer.

In the drawing-herewith, Fig, 1 is a central vertical section throughthe upper end of the apparatus employed in my invention. Fig. 2 is asimilar view illustrating the lower end of the casing andeduction tube.

The well casing 1' extends from ,the lower end of the well adjacent theproducing formation to the surface and has thereon a casing head 2 ofspecial construction. This casing head i has a lateral connection 3through which gas may be admitted to or allowed to escape from the wellas desired. Above this lateral opening the casing head has an interior,shoulder 4 upon which is supported the head 5 connected with theeduction tube 6., At the upper end of the casing head is secured abonnet7, the reduced upper end of which is threaded interiorly at 8 forconnection with theupper extension 9 upon the eduction tube. Thecasinghas a lateral outlet 10 from the inner chamber 11 in the casinghead and bonnet, through which the liquid 1 from the well' escapes tostorage. Lateral handles 12 upon the bonnet are provided for thepurposes of assembly. I y

The eduction tube 6 is connected at its lower end with a downwardlyswaged'nipple 13, the -o0 lower endof whichis connected at 14' to anextension 15 of materially smaller diameter. Within the nipple 13 is across-shaped stop member 16 against which the plunger may contact. Y j 4The reduced extension 15 is projected downwardly beneath the level ofthe liquid in the well to the desired' degree of submerge-nee. It hasupon its lower end a perforated bull plug 17 providing a strainer for #0the fluid entering the tube. a I

Above the lower end of the extension 15 1 provide a packer to seal thespace between the tube and the inner wall of the casing. This packer maybe of any desired form. I "I5 1 have shown two spaced cups 18 offlexible material such 'as rubber. These cups are faced toward eachother and are supported on their remotesides by cups 19'of metal securedrigidlyto the pipe. Between the two rubber cups 18 is a spacing sleeve20 holding the cups apart and securing them in position within thereenforcing cups 19. I prefer to form a slight vent 21 inthe upper andlower packing sleeves to allow a slight lealrage of gas past the packerso as to-maintaln approximately equal gas pressures on both sides of thepacker. This packer is ordinarily placed below the liquid level in thewell and provides a space below it into'which the gas may accumulate.The liqui d is gradually forced past the packer into the lowerend of thewell by the accumulation of gas in the casing.

However, the leakage of gas past the packer will. be so slow that itwill not materially affect the quick'accumulation of suflicient gaspressure in the small space provided below the packer in the'operationof the device.

The upper end of the eduction tube is connected to the head 5 which hasa radial flange thereon fitting closely within the casing head andresting upon a packing gasket 22 to form a seal at that point preventingthe escape of gas from the well past the head.

At the upper end of the head the interior is formed to make aclose fitwith the lower end of the extension 9 of the eduction tube. As thisextension has to be screwed downwardly when the bonnet is mounted inposition no thread is formed upon the extension at this point. The upperend of the head is provided with a threaded nipple 23 to which may besecured a setting device by means of which the tube is lowered onto theseat 4. The extension is provided with openings 24 within the casinghead to allow the escape of fluid in the operation of the device. Theupper end of the extension is closed by acap 25 forming a dead end inthe tube to receive fluid from the well and to allow the entrance of theplunger during the operation of the device.

The plunger 26 is of the usual type comprising a body having adownwardly converging passage therethrough with a valve 27 closingupwardly into the seat 28. The valve is normally supported upon anextension 29 having a guide opening therethrough for the valve stem 30,which contacts with the stop member 16 and forces the valve to closedposition.

In the operation of the device the liquid tends to rise upwardly in theeduction tube due to hydrostatic pressure and is assisted in its flowinginto the tube by the bubbles of gas coming from the producing formation.Where the tube is of larger diameter the bubbles of gas may slip by theliquid and have very little lifting effect, but where the tube is ofsmall diameter there is less slippage of the gas relative to the liquidand a pronounced lifting effect is obtained which is desirable in thelifting operation of the device. Further, by accumulating the gas belowthe packer 19 it is not necessary to raise the pressure within the wholeinterior of the casing but only within the small chamber below thepacker and the liquid will therefore be forced upwardly past the seat 16into the eduction tube and a. suflicient head will h ave accumulatedabove the seat for the desired load by the time the plunger has droppedfrom the surface to the seat. 7

The accumulation of gas will raise the plunger with its load to thesurface, the load of liquid being discharged through the openings :24and the outlet 10 to storage. When the plunger reaches these openings 24it will. be forced past the openings by the gas pressure into theextension 9 and the valve will be moved to open position by the backpressure of the fluid compressed in said extension. The gas will escapebehind the plunger, allowing the plunger to fall with the valve open tothe bottom, and by the time it has reached the lower end of the tube theliquid will have risen above the seat 16 to provide sufficient load forthe next stroke.

The advantages of this construction lie in the fact that the smallamount of gas in the well is enabled to have a marked lifting effect toraise the level of the liquid in the eduction tube before the plungerreaches bottom, where without this reduced. extension upon the tube theplunger might reach bottom before sufficient load had accumulated abovethe seat and would thus be damaged by dropping upon a dry seat. Further,by use of this device-the level of the liquid may be maintained in thetube without setting the eduction tube upon the bottom. of the well,that is, a smaller submergence can be employed and still obtaineffective operation of the device. By operating oft bottom the inclusionof salt water or other undesirable elements lat the bottom of the wellmay be avoided. Further, the lower extension will act to prevent theaccumulation of large bubbles or charges of gas in the oil, in. that itwill feed the gas to the eduction tubemore gradually, allowing the oilto enter therewith.

What I claim as new is:

1. A plunger lift pump including a well casing, an eduction tube in saidcasing extending from the surface to a level spaced materially above thebottom of the well, a plunger in said eduction tube, a stop for saidplunger at thelower end of said tube, an extension of smaller diameterthan said tube on the lower end thereof extending below the liquidlevel, and a sealing means between said extension and said casing abovethe lower end thereof.

2. A plunger lift pump including a well casing, an eduction tube in saidcasing extending from the surface to a level spaced materially above thebottom of the well, a plunger in said eduction tube, a stop for saidplunger at the lower end of said tube, an extension of smaller diameterthan said tube on the lower end thereof projecting downwardly to theliquid level, and a packer on said extension adjacent its lower end.

3. A plunger lift pump including a well casing, an eduction tube thereinextending from the upper end thereof to a point below the surface of theliquid in the well, an extension of materially smaller diameter on saidtube, the lower end of which has a perforated inlet member thereon, apacker on said exten- .sion closing off the space between said extensionand said casing, a plunger movable the length of said tube, and means toclose the space in the upper end of said casing about said tube.

4. A plunger lift pump including a well casing, an eduction tube thereinextending from the upper end thereof to a point below the surface of theliquid in the well, an extension of materially smaller diameter on saidtube whereb the as in the well may more effectively e evate iquid insaid extension to the eduction tube, a. packer on said extension and aplunger inrsaid tube.

In testimony whereof, I hereunto aflix my signature this the 5th day ofJanuary A. D.,

NORMAN H. RICKER.

